code: def test_compute_pairs(n_rows, n_cols, n):
      """Test computation of S-D pairings."""
      want = KNOWN_PAIRS[(n_rows, n_cols, n)]
      got = _compute_pairs(n_rows, n_cols, n)
      assert got == want
  
file_path: mne-python/mne/io/hitachi/tests/test_hitachi.py
imports: import datetime
  import numpy
  import pytest
  from numpy.testing import assert_allclose, assert_array_less
  from mne.channels import make_standard_montage
  from mne.io import read_raw_hitachi
  from mne.io.hitachi.hitachi import _compute_pairs
  from mne.io.tests.test_raw import _test_raw_reader
  from mne.preprocessing.nirs import beer_lambert_law, optical_density, scalp_coupling_index, source_detector_distances, tddr
label_desc: Use image node_id 2 for calling a global function with example usage: test_compute_pairs(n_rows, n_cols, n) without return types